Structural Alterations in the Translational Attenuator of Constitutively Expressed <b> <i>erm</i> (A) Genes in <i>Staphylococcus aureus</i> </b>

Abstract

The expression of the predominant macrolide resistance genes in staphylococci, erm(A) and erm(C) (2, 7), is either inducible by 14- and 15-membered macrolides via translational attenuation or constitutive. Constitutively expressederm(A) and erm(C) genes are of particular clinical relevance since they also confer resistance to 16-membered macrolides, lincosamides, streptogramin B antibiotics, and the new ketolide drugs. To date, very few data on the molecular basis of constitutive erm(A) gene expression in naturally occurring staphylococci are available (8).